From: Miaohe Lin <linmiaohe@huawei.com>
To: Oscar Salvador <osalvador@suse.de>, Rik van Riel <riel@surriel.com>
Cc: <linux-kernel@vger.kernel.org>, <kernel-team@fb.com>,
<linux-mm@kvack.org>, Andrew Morton <akpm@linux-foundation.org>,
Mel Gorman <mgorman@suse.de>,
Johannes Weiner <hannes@cmpxchg.org>,
Matthew Wilcox <willy@infradead.org>
Subject: Re: [PATCH v2] mm: clean up hwpoison page cache page in fault path
Date: Wed, 16 Feb 2022 10:13:14 +0800 [thread overview]
Message-ID: <e6eeb84f-cf1d-493e-ce8e-fea6f3679a9e@huawei.com> (raw)
In-Reply-To: <Yguh5JUGHln/iRJ8@localhost.localdomain>
On 2022/2/15 20:51, Oscar Salvador wrote:
> On Sat, Feb 12, 2022 at 09:37:40PM -0500, Rik van Riel wrote:
>> Sometimes the page offlining code can leave behind a hwpoisoned clean
>> page cache page. This can lead to programs being killed over and over
>> and over again as they fault in the hwpoisoned page, get killed, and
>> then get re-spawned by whatever wanted to run them.
>
> Hi Rik,
>
> Do you know how that exactly happens? We should not be really leaving
> anything behind, and soft-offline (not hard) code works with the premise
> of only poisoning a page in case it was contained, so I am wondering
> what is going on here.
>
> In-use pagecache pages are migrated away, and the actual page is
> contained, and for clean ones, we already do the invalidate_inode_page()
> and then contain it in case we succeed.
>
IIUC, this could not happen when soft-offlining a pagecache page. They're either
invalidated or migrated away and then we set PageHWPoison.
I think this may happen on a clean pagecache page when it's isolated. So it's !PageLRU.
And identify_page_state treats it as me_unknown because it's non reserved, slab, swapcache
and so on ...(see error_states for details). Or am I miss anything?
Thanks.
> One scenario I can imagine this can happen is if by the time we call
> page_handle_poison(), someone has taken another refcount on the page,
> and the put_page() does not really free it, but I am not sure that
> can happen.
>
next prev parent reply other threads:[~2022-02-16 2:13 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-02-13 2:37 [PATCH v2] mm: clean up hwpoison page cache page in fault path Rik van Riel
2022-02-14 23:24 ` Andrew Morton
2022-02-15 1:37 ` Rik van Riel
2022-02-15 5:15 ` HORIGUCHI NAOYA(堀口 直也)
2022-02-15 11:22 ` David Hildenbrand
2022-02-15 15:01 ` Rik van Riel
2022-02-15 15:06 ` David Hildenbrand
2022-02-15 12:51 ` Oscar Salvador
2022-02-15 15:04 ` Rik van Riel
2022-02-16 2:13 ` Miaohe Lin [this message]
2022-02-21 12:54 ` Oscar Salvador
2022-02-21 13:19 ` Miaohe Lin
2022-02-21 12:55 ` Oscar Salvador
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=e6eeb84f-cf1d-493e-ce8e-fea6f3679a9e@huawei.com \
--to=linmiaohe@huawei.com \
--cc=akpm@linux-foundation.org \
--cc=hannes@cmpxchg.org \
--cc=kernel-team@fb.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=mgorman@suse.de \
--cc=osalvador@suse.de \
--cc=riel@surriel.com \
--cc=willy@infradead.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).